The present invention is related to electrodeless discharge lamp operating apparatuses, electrodeless compact self-ballasted fluorescent lamps and discharge lamp operating apparatuses, and more particularly relates to an operating apparatus for controlling light with an incandescent lamp dimmer.
Fluorescent lamps have higher efficiency and a longer lifetime than incandescent lamps. Therefore, fluorescent lamps are now widely used in view of global environmental protection and also for economical reason. Moreover, in recent years, compact self-ballasted fluorescent lamps in which a fluorescent lamp and a ballast circuit are assembled as one unit have attracted attention as an energy conservation type light source for use in houses, hotels, restaurants and the like. Besides, a compact self-ballasted fluorescent lamp as it is can be used easily in place of an incandescent lamp. Therefore, use of compact self-ballasted fluorescent lamps is apparently going to spread more and more.
Furthermore, electrodeless compact self-ballasted fluorescent lamps which do not include an electrode recently draw attention as an economical light source because their lifetime is several times longer than that of known compact self-ballasted fluorescent lamps which include an electrode. Thus, the demand for electrodeless compact self-ballasted fluorescent lamps shows a tendency of an increase.
Meanwhile, in houses and hotels, people read books, enjoy family time, and perform various other living activities. For a comfortable lighted environment suitable to such living activities, it is required to provide light of appropriate brightness for each scene. In the case of an incandescent lamp, the brightness of light can be controlled in a simple manner by using a commercially-available incandescent lamp incandescent lamp dimmer. As for dimming of an incandescent lamp, it is general to use a technique in which the brightness of light is controlled by turning ON/OFF a commercial power voltage to alter an ON period of an incandescent lamp, i.e., a technique in which a phase-controlled voltage is input to an incandescent lamp using an incandescent lamp dimmer. On the other hand, in the case of a compact self-ballasted fluorescent lamp, it is also required to change the brightness of light using an existing incandescent lamp dimmer in the same manner as in the case of an incandescent lamp. However, since light of a fluorescent lamp is generated by discharge, unlike an incandescent lamp, it is difficult to achieve a practically usable, dimmable fluorescent lamp by simply controlling power supply.
Recently, to meet needs from users for controlling the brightness of light with an existing incandescent lamp dimmer in the same manner as in the case of an incandescent lamp, an electrode-including compact self-ballasted fluorescent lamp which can be connected to an incandescent lamp dimmer to perform dimming was developed (Japanese Unexamined Patent Publication No. 11-111486). However, under the present circumstances, a dimmable electrodeless compact self-ballasted fluorescent lamp has still not been developed.
Moreover, when dimming of the dimmable electrode-including compact self-ballasted fluorescent lamp is performed, the electrode-including compact self-ballasted fluorescent lamp is connected to a commercially available incandescent lamp dimmer and used in many cases. In such cases, dimming of the electrode-including compact self-ballasted fluorescent lamp can be in principle performed with any incandescent lamp dimmer as a commercially available incandescent lamp dimmer. However, depending on incandescent lamp dimmers, a dimming operation of a lamp can not be normally performed and inconveniences such as flickering or difficulties in operating the lamp might be caused. This is what the present inventors found through actual experiments.
To solve the above-described problems, the present invention has been devised. Therefore, it is an object of the present invention to provide an electrodeless discharge lamp operating apparatus, an electrodeless compact self-ballasted fluorescent lamp operating apparatus and a discharge lamp operating apparatus in which flickering and a difficulty in operating are prevented and stable dimming operation is achieved.
Moreover, it is another object of the present invention to supply electrical energy during an entire conduction period of a phase-controlled voltage to operate a discharge lamp so that a dimming range is increased to a larger size than that of a known lamp operating apparatus.
An electrodeless discharge lamp operating apparatus in accordance with the present invention includes: an electrodeless discharge lamp; an AC/DC conversion unit for converting an alternating current voltage phase-controlled by a dimmer into a direct current voltage; a DC/AC conversion unit for converting the direct current voltage into a high frequency voltage and driving, with the high frequency voltage, the electrodeless discharge lamp so that the electrodeless discharge lamp performs an intermittent operation including an operation period in which the electrodeless discharge lamp is operated and a non-operation period in which the electrodeless discharge lamp is turned OFF; and a dimming control unit for outputting to the DC/AC conversion unit a dimming instruction signal for changing the ratio between the operation period and the non-operation period, and the dimming control unit detects turn-ON and turn-OFF of the phase-controlled alternating voltage and substantially synchronizes the timings of the turn-ON and the turn-OFF with the start timings of the operation period and non-operation period of the intermittent operation by the DC/AC conversion unit, respectively.
In one preferred embodiment of the present invention, the DC/AC conversion unit drives the electrodeless discharge lamp so that the electrodeless discharge lamp performs an intermittent operation including an operation period in which the high frequency voltage is applied to the electrodeless discharge lamp to operate the electrodeless discharge lamp and a non-operation period in which the generation of the high frequency voltage is stopped to turn OFF the electrodeless discharge lamp.
Moreover, in another preferred embodiment of the present invention, the DC/AC conversion unit drives the electrode discharge lamp so that the electrode discharge lamp performs an intermittent operation including an operation period in which the direct current voltage is converted into a high frequency voltage with which the electrodeless discharge lamp is operated and then applied to the electrodeless discharge lamp and a non-operation period in which the direct current voltage is converted into a high frequency voltage with which the electrodeless discharge lamp is not operated and then applied to the electrodeless discharge lamp.
Furthermore, in still another preferred embodiment of the present invention, the DC/AC conversion unit includes at least one switching element and drives by changing a voltage between gate and source of the switching element, when the direct current voltage is converted into a high frequency voltage and then applied to the electrodeless discharge lamp, the electrodeless discharge lamp so that the electrodeless discharge lamp performs an intermittent operation including an operation period in which the electrodeless discharge lamp is operated and a non-operation period in which a less amount of current is passed in the electrodeless discharge lamp than that in the operation period to turn OFF the electrodeless discharge lamp.
Moreover, it is preferable that the dimming control unit includes a photocoupler as means for transmitting the dimming instruction signal to the DC/AC conversion unit.
An electrodeless compact self-ballasted fluorescent lamp includes: an electrodeless fluorescent lamp; a ballast circuit for applying a high frequency voltage to the electrodeless fluorescent lamp; and a base electrically connected to the ballast circuit, the electrodeless fluorescent lamp, the ballast circuit and the base are assembled as one unit, the ballast circuit includes: an AC/DC conversion unit for converting an alternating current voltage phase-controlled by a dimmer into a direct current voltage and outputting the converted voltage; a DC/AC conversion unit for converting the direct current voltage into a high frequency voltage and driving, with the high frequency voltage, the electrodeless discharge lamp so that the electrodeless discharge lamp performs an intermittent operation including an operation period in which the electrodeless discharge lamp is operated and a non-operation period in which the electrodeless discharge lamp is turned OFF; and a dimming control unit for outputting to the DC/AC conversion unit a dimming instruction signal for changing the ratio between the operation period and the non-operation period, and the dimming control unit detects turn-ON and turn-OFF of the phase-controlled alternating voltage and substantially synchronizes the timings of the turn-ON and the turn-OFF with the start timings of the operation period and non-operation period of the intermittent operation of the DC/AC conversion unit, respectively.
It is preferable that the dimming control unit includes a dimming signal input unit for inputting the alternating current voltage phase-controlled by the dimmer, a photocoupler connected to the dimming signal input unit, and a dimming instruction signal unit for transmitting the dimming instruction signal from the photocoupler to the DC/AC conversion unit.
A first discharge lamp operating apparatus in accordance with the present invention includes: a discharge lamp; an AC/DC conversion unit for converting an alternating current voltage phase-controlled by a dimmer into a direct current voltage and outputting the converted voltage; a DC/AC conversion unit for converting the direct current voltage into a high frequency voltage and driving the discharge lamp so that the discharge lamp performs an intermittent operation including an operation period in which the high frequency voltage is applied to operate the discharge lamp and a non-operation period in which the generation of the high frequency voltage is stopped to turn OFF the discharge lamp; and a dimming control unit for outputting to the DC/AC conversion unit a dimming instruction signal for changing the ratio between the operation period and the non-operation period, and the dimming control unit detects turn-ON and turn-OFF of the phase-controlled alternating voltage and keeps a difference between the timing of the turn-ON and the start timing of the operation period of the intermittent operation by the DC/AC conversion unit and a difference between the timing of the turn-OFF and the start timing of the non-operation period of the intermittent operation by the DC/AC conversion unit constant.
A second discharge lamp operating apparatus in accordance with the present invention includes: a discharge lamp; an AC/DC conversion unit for converting an alternating current voltage phase-controlled by a dimmer into a direct current voltage and outputting the converted voltage; a DC/AC conversion unit for driving the discharge lamp so that the discharge lamp performs an intermittent operation including an operation period in which the direct current voltage is converted into a high frequency voltage with which the electrodeless discharge lamp is operated and then applied to the discharge lamp and a non-operation period in which the direct current voltage is converted into a high frequency voltage with which the discharge lamp is not operated and then applied to the discharge lamp; a dimming control unit for outputting to the DC/AC conversion unit a dimming instruction signal for changing the ratio between the operation period and the non-operation period, and the dimming control unit detects turn-ON and turn-OFF of the phase-controlled alternating voltage and keeps a difference between the timing of the turn-ON and the start timing of the operation period of the intermittent operation by the DC/AC conversion unit and a difference between the timing of the turn-OFF and the start timing of the non-operation period of the intermittent operation by the DC/AC conversion unit constant.
A third discharge lamp operating apparatus in accordance with the present invention includes: a discharge lamp; an AC/DC conversion unit for converting an alternating current voltage phase-controlled by a dimmer into a direct current voltage and outputting the converted voltage; a DC/AC conversion unit which includes at least one switching element and drives by changing a voltage between gate and source of the switching element, when the direct current voltage is converted into a high frequency voltage and then applied to the discharge lamp, the discharge lamp so that the discharge lamp performs an intermittent operation including an operation period in which the discharge lamp is operated and a non-operation period in which a less amount of current is passed in the discharge lamp than that in the operation period to turn OFF the discharge lamp; a dimming control unit for outputting to the DC/AC conversion unit a dimming instruction signal for changing the ratio between the operation period and the non-operation period, the dimming control unit detects turn-ON and turn-OFF of the phase-controlled alternating voltage and keeps a difference between the timing of the turn-ON and the start timing of the operation period of the intermittent operation by the DC/AC conversion unit and a difference between the timing of the turn-OFF and the start timing of the non-operation period of the intermittent operation by the DC/AC conversion unit constant.
In one preferred embodiment of the present invention, the dimming control unit detects turn-ON and turn-OFF of the phase-controlled alternating voltage and keeps a difference between the timing of the turn-ON and the start timing of the operation period of the intermittent operation by the DC/AC conversion unit and a difference between the timing of the turn-OFF and the start timing of the non-operation period of the intermittent operation by the DC/AC conversion unit substantially 0.
Moreover, in another preferred embodiment of the present invention, the dimming control unit includes a photocoupler as means for transmitting the dimming instruction signal to the DC/AC conversion unit.
Furthermore, in still another preferred embodiment of the present invention, characterized in that the discharge lamp is an electrode-including fluorescent lamp.